HLA-DRB1*15:01 and HLA-DRB3*02:02 in PLA2R-Related Membranous Nephropathy.

Idiopathic membranous nephropathy (MN) is associated with HLA; however, the HLA allele involved remains unknown. To identify the HLA risk alleles associated with phospholipase A2 receptor (PLA2R)-related MN in the Chinese population, we sequenced the entire MHC region in DNA samples from 99 patients with PLA2R-related MN, 50 patients with PLA2R-unrelated MN, and 100 healthy subjects. Two HLA risk alleles, HLA-DRB1*15:01 and HLA-DRB3*02:02, independently and strongly associated with an increased risk of PLA2R-related MN. After adjusting for HLA-DRB1*15:01 and HLA-DRB3*02:02, no other alleles showed significant association with PLA2R-related MN. A replication study in an independent cohort of 293 participants with PLA2R-related MN and 285 healthy controls validated these findings. In a joint analysis, a multivariate logistic regression model confirmed that HLA-DRB1*15:01 (odds ratio [OR], 24.9; 95% confidence interval [95% CI], 15.3 to 42.6; P=2.3×10-35) and HLA-DRB3*02:02 (OR, 17.7; 95% CI, 11.0 to 30.3; P=8.0×10-29) independently and strongly associated with PLA2R-related MN. As many as 98.7% of patients with PLA2R-related MN, compared with 43.9% of control subjects, carried at least one HLA risk allele. Subjects with either risk allele had higher odds of developing PLA2R-related MN than those without a risk allele (OR, 98.9; 95% CI, 44.4 to 281.7; P=2.5×10-23). These HLA risk alleles also associated with the age at disease onset in patients with PLA2R-related MN. In conclusion, our findings provide clear evidence that the HLA-DRB1*15:01 and HLA-DRB3*02:02 alleles independently and strongly associate with PLA2R-related MN in the Chinese population.

Evaluating tacrolimus treatment in idiopathic membranous nephropathy in a cohort of 408 patients.

BACKGROUND: The KDIGO Clinical Practice Guidelines for Glomerulonephritis recommended tacrolimus as an alternative regimen for the initial therapy for Idiopathic membranous nephropathy (IMN), however, large observational studies evaluating tacrolimus treatment in IMN remains rare. METHODS: A total of 408 consecutive IMN patients with nephrotic syndrome who were treated with tacrolimus in Jinling Hospital were included. The effectiveness and safety of tacrolimus treatment in IMN were analyzed in this study. RESULTS: The cumulative partial or complete remission after tacrolimus therapy were 50%, 63% and 67% at 6, 12 and 24 months, respectively, and the cumulative complete remission rates were 4%, 13% and 23%, respectively. Multivariate logistic analysis showed that higher tacrolimus exposure during induction treatment, female gender, higher eGFR and no history of previous immunosuppressive therapy were independently associated with higher probability of remission. A relapse occurred in 101 of the 271 (37.3%) patients with partial or complete remission, and 18 of the 95 (18.9%) patients with complete remission. Tapering duration of tacrolimus and complete remission versus partial remission status were independent factors associated with risk of relapse. A decline in eGFR was the most frequent adverse event during tacrolimus treatment. During tacrolimus treatment, a ≥40% decrease in eGFR was observed in 43 (10.5%) patients. CONCLUSIONS: Low dose tacrolimus is effective for IMN, with a total remission rate of 66% whereas with a rather high rate of relapse. However, the safety of tacrolimus treatment needs to be further validated in large randomized clinical trials.

Combined Assessment of Phospholipase A2 Receptor Autoantibodies and Glomerular Deposits in Membranous Nephropathy.

Serum phospholipase A2 receptor antibodies (SAbs) and glomerular phospholipase A2 receptor antigen (GAg) deposits have been observed in idiopathic membranous nephropathy (IMN). However, the clinical application of these two biomarkers, particularly GAg deposition, needs to be further evaluated. We measured SAb concentration by ELISA and GAg deposition by immunofluorescence in 572 patients with biopsy-proven IMN. Overall, 68.5% of patients (392 of 572) had detectable SAb (SAb+), and 98.7% of patients who were SAb+ (387 of 392) and 70.6% of patients who were SAb- (127 of 180) had GAg deposition (GAg+). Compared with patients who were SAb-/GAg+, patients who were SAb+/GAg+ exhibited higher levels of proteinuria (P<0.001) and a lower chance of proteinuria remission (P<0.001). In 52 patients who underwent repeat biopsies, patients who did not achieve remission had a higher SAb+ rate on the first biopsy than patients who went into remission (P=0.001). Furthermore, SAb+ levels persisted in patients who did not achieve remission but significantly decreased in patients who achieved remission by the second biopsy. Patients who did not achieve remission also had a higher GAg+ rate on the first biopsy than patients who achieved remission (P<0.01). Sustained GAg+ deposits correlated with disease relapse. In conclusion, combining the measurements of SAb levels and detection of GAg deposition may provide additional information regarding diagnoses, treatment response, and disease relapse in patients with IMN.